How to Tell If Your Dog Has a Medially Luxating Patella
Learn how to recognize signs of medial patellar luxation in dogs early, including limping, clicking sounds, and changes in gait for timely treatment

What Is Medial Patellar Luxation in Dogs?
Medial Patellar Luxation (MPL) is a condition where the kneecap (patella) slips out of its normal groove toward the inside of a dog’s leg. This causes the knee joint to become unstable, leading to pain, limping, and difficulty walking. MPL is especially common in small and toy dog breeds but can affect dogs of any size.
MPL matters because if left untreated, it can cause long-term joint damage, arthritis, and chronic pain. The slipping kneecap puts extra stress on the knee, making movement uncomfortable and sometimes causing your dog to avoid using the leg.
Early detection is very important for your dog’s health and comfort. Recognizing signs like limping, skipping steps, or holding up a leg allows you to seek veterinary care sooner. Early treatment can reduce pain, prevent further damage, and improve your dog’s quality of life. Keeping a close eye on your dog’s movement helps catch MPL before it worsens.
Common Signs That Your Dog May Have MPL
Here are some common signs that can help you identify if your dog may be suffering from medial patellar luxation (MPL).
1. Limping or Skipping Steps
Limping or skipping steps is one of the earliest signs your dog might have medial patellar luxation (MPL). When the kneecap slips out of place, your dog may feel pain or instability, causing uneven movement.
- Watch for your dog lifting a leg briefly while walking or running.
- Notice if your dog skips steps or hops on one leg suddenly.
- Limping can be subtle at first and may only happen after exercise or prolonged activity.
If you see your dog favoring one leg or walking unevenly, it’s a sign to check with your vet. Early limping or skipping indicates discomfort or instability in the knee, which can worsen if untreated. Tracking these patterns helps you catch MPL early and get your dog the care needed to prevent long-term damage.
2. Intermittent or Persistent Lameness
Lameness means your dog is limping or not using a leg normally. It can be intermittent (comes and goes) or persistent (constant). Both can be warning signs of MPL.
- Intermittent lameness often appears after exercise or activity when the kneecap slips out temporarily.
- Persistent lameness means ongoing pain or instability in the knee, which needs urgent attention.
- Your dog may hold up the leg or limp constantly if the condition is severe.
Recognizing when lameness changes from occasional to frequent is important. Early veterinary diagnosis can help treat mild lameness before it becomes severe. Persistent lameness might indicate worsening MPL or other complications. Watching how often your dog limps and seeking veterinary advice quickly improves treatment outcomes.
3. Abnormal Gait or Skipping Leg Movement
An abnormal gait means your dog’s walk or run looks different from normal. In dogs with MPL, this often shows as unusual skipping or jerky leg movement.
- Your dog may appear to skip or hop instead of walking smoothly.
- The affected leg might move differently, seeming stiff or shaky.
- This irregular movement happens because the kneecap slips, causing discomfort or instability.
This gait change may be subtle at first and can be mistaken for other issues. Watching carefully during walks or play helps spot unusual leg movements. Early detection allows for prompt treatment to restore normal walking patterns and reduce pain.
4. Audible Clicking or Popping Sounds
Clicking or popping sounds from your dog’s knee are signs that the kneecap is moving abnormally. These sounds happen when the patella slips out of its groove and snaps back.
- You might hear a faint “click” when your dog walks, runs, or moves the leg.
- These noises show joint instability and possible damage to soft tissues.
- Not all dogs make these sounds, but if you hear them often, it’s a sign to get a vet check.
Listening for these sounds during activity or when your dog moves the leg gently can provide clues about MPL. Early veterinary diagnosis helps prevent joint damage from frequent slipping.
5. Visible or Palpable Slipping of the Kneecap
Sometimes, you can see or feel the kneecap slipping out of place. This popping or luxation happens when the kneecap moves out of its normal groove on the thigh bone.
- Gently feel your dog’s knee when the leg is bent and straightened to check for slipping.
- You might see the kneecap visibly move or pop to the side during leg movement.
- If unsure, have a vet perform this test to avoid causing pain or injury.
Feeling or seeing the patella slip is a clear sign of MPL. If you notice this, it’s important to visit your vet for a full examination and diagnosis.
6. Holding Up the Leg or Avoiding Weight Bearing
Dogs with MPL often hold up the affected leg or avoid putting weight on it to relieve pain or discomfort.
- Your dog may lift the leg while standing or walking, especially after activity.
- Avoidance of weight bearing is a common way dogs protect an injured or painful knee.
- This behavior can be temporary or frequent depending on MPL severity.
If your dog regularly holds up a leg or refuses to walk on it, it’s a strong sign of knee pain. Early vet evaluation helps manage discomfort and improves healing.
7. Difficulty or Reluctance to Jump, Run, or Climb Stairs
Changes in your dog’s activity level, like difficulty or unwillingness to jump, run, or climb stairs, often point to knee problems like MPL.
- Your dog may avoid stairs or hesitate before jumping onto furniture or into cars.
- Running or playing less than usual can indicate discomfort during high-impact activities.
- These behavioral changes help protect the painful knee from stress.
Noticing reluctance to be active is important for early MPL detection. Discussing these changes with your vet can lead to timely diagnosis and treatment.
8. Swelling or Pain Around the Knee Joint
Swelling or pain near the knee joint may develop with MPL due to inflammation from repeated kneecap slipping.
- Look for visible swelling, warmth, or tenderness around the knee.
- Your dog might lick or chew the knee area more than usual.
- Pain signs include limping, whining, or reluctance to move.
Swelling and pain indicate irritation or early joint damage. Prompt veterinary care can reduce inflammation and prevent progression.
9. Changes in Behavior Like Reluctance to Play or Exercise
Discomfort from MPL often causes changes in your dog’s behavior, such as reduced playfulness or exercise reluctance.
- Your dog may become less active or hide more than usual.
- Decreased interest in walks, toys, or interaction can signal pain.
- These subtle mood changes are important clues to underlying knee issues.
Recognizing these behavior shifts early helps you seek veterinary care and improve your dog’s comfort and quality of life.
How MPL Symptoms Can Worsen Over Time
If medial patellar luxation (MPL) is not treated, your dog’s symptoms can get worse and cause more serious problems.
- More frequent kneecap slipping: The patella may move out of place more often, causing pain and joint instability.
- Joint damage and arthritis: Repeated slipping can wear down cartilage and bones, leading to arthritis. This causes swelling, stiffness, and long-term pain.
- Increased limping or holding up the leg: Your dog may limp more or avoid using the affected leg due to discomfort.
- Posture and gait changes: To reduce pain, your dog might change how they stand or walk, which can cause muscle loss and strain on other legs.
- Both knees affected: Sometimes MPL develops in both legs, worsening mobility and quality of life.
Monitoring your dog’s symptoms closely helps catch these changes early. Watch for increased limping, reduced activity, or changes in behavior. Early vet care can reduce pain, prevent joint damage, and improve your dog’s chances of a happy, active life.
How to Monitor Your Dog’s Mobility and Pain at Home
Monitoring your dog’s mobility and pain at home helps you track their condition and notice any worsening signs early. Regular observation lets you provide important information to your vet for better care.
- Watch your dog’s walking: Look for limping, skipping steps, or difficulty standing up. Notice if your dog favors one leg or hesitates to move.
- Observe activity levels: Pay attention to changes in how much your dog wants to play, run, or climb stairs. Reduced activity can signal pain or discomfort.
- Check for stiffness: Notice if your dog is stiff or slow to get moving after resting or sleeping.
- Look for pain behaviors: Whining, licking the knee, or sudden stops during movement may show discomfort.
- Examine posture: Watch for changes in how your dog holds their leg or stands.
Keep a simple journal to record daily observations, noting any new or worsening symptoms. Include details about when symptoms appear, their severity, and any triggers like exercise. Sharing this information with your vet helps tailor treatment and improves your dog’s care. Regular monitoring is key to managing MPL effectively.
When to Seek Veterinary Care for Suspected MPL
Knowing when to seek veterinary care for suspected medial patellar luxation (MPL) is crucial to protect your dog’s health and comfort. Early veterinary attention can prevent worsening damage and reduce pain.
- Sudden or severe limping: If your dog starts limping suddenly or cannot put weight on a leg, it needs immediate vet care.
- Persistent or worsening lameness: Continuous limping or increasing difficulty walking are signs of serious knee issues.
- Visible swelling or redness: Swelling, heat, or redness around the knee may indicate inflammation or infection.
- Audible clicking or popping: Hearing frequent clicking sounds from the knee can signal instability needing professional evaluation.
- Reluctance to move or play: A sudden decrease in activity or reluctance to jump, run, or climb stairs suggests discomfort.
Early diagnosis allows your vet to assess the severity of MPL and recommend the best treatment, whether conservative care or surgery. Prompt treatment reduces pain, slows joint damage, and improves your dog’s quality of life. Don’t wait for symptoms to worsen—early veterinary care is key to a better outcome.
FAQs About How to Tell If Your Dog Has a Medially Luxating Patella
What is medial patellar luxation in dogs?
Medial patellar luxation (MPL) occurs when the kneecap slips out of its normal position toward the inside of the leg. It causes pain, limping, and joint instability. It’s common in small breeds but can affect all dogs. Early detection is key to preventing long-term damage.
How can I spot limping caused by MPL?
Limping or skipping steps may happen suddenly or after activity. Your dog might lift or favor one leg, showing discomfort. Limping can be subtle at first, so careful observation during walks is important to catch early signs of MPL.
What does an abnormal gait look like in dogs with MPL?
An abnormal gait may appear as skipping, hopping, or uneven leg movement. The affected leg might move stiffly or jerk unexpectedly due to the kneecap slipping out of place, causing discomfort and instability while walking or running.
Why does my dog’s knee make clicking sounds?
Clicking or popping noises occur when the kneecap moves out and back into its groove. These sounds indicate joint instability and frequent slipping of the patella. Hearing this often suggests your dog should be checked by a vet.
How can I check if my dog’s kneecap is slipping?
Gently feel your dog’s knee while moving the leg to detect popping or slipping of the kneecap. Be careful to avoid causing pain. If unsure, let a vet perform the test safely for an accurate diagnosis.
When should I take my dog to the vet for suspected MPL?
Visit the vet if your dog shows limping, skipping steps, leg holding, swelling, or audible knee clicks. Early veterinary care is important to diagnose MPL, start treatment, and prevent worsening symptoms and joint damage.
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